ARTICLE

The 5 Whys Analysis

Drilling down to systemic root causes.

Beyond Symptoms

When a defect occurs, it is easy to blame the operator. However, the root cause is almost always systemic.

By asking "Why?" repeatedly (typically 5 times), we move past the symptom and find the flaw in the process or standard.

1. Why did the machine stop? (Overload blew the fuse)

2. Why was there an overload? (The bearing was not sufficiently lubricated)

3. Why was it not lubricated? (The lubrication pump was not pumping sufficiently)

4. Why was it not pumping? (The shaft of the pump was worn and rattling)

5. Why was the shaft worn? (There was no strainer attached and metal scrap got in) - ROOT CAUSE